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131.
Three abortigenic Indian isolates of equine herpesvirus-1 (EHV-1) (Tohana, Hisar and Bikaner), along with two exotic abortigenic
isolates (AB4 and V592) and another EHV-1 isolate (Jind) obtained from a case of perinatal foal mortality, were studied for
variability. For this purpose, PCR and restriction endonuclease (RE) digestion techniques were used simultaneously as a DNA
fingerprinting system. Nine different regions of EHV-1 virus were amplified by PCR using primer pairs specific for the regions
and the products obtained from these regions were subsequently subjected to various restriction endonucleases to further assess
the variability in the number of RE sites as well as in their positions. No difference was observed in all the four abortigenic
isolates in terms of the size of different PCR products amplified by all the nine primer pairs, except for primer pairs ‘E’
and ‘C’. PCR products obtained with primer pair E revealed that Tohana and Bikaner isolates were most similar while Hisar
isolate was like V592 isolate. However, the PCR product obtained from Jind isolate had a size between the PCR products of
Hisar and Tohan/Bikaner isolates. The primer pair ‘C’ used to amplify the region between 1151 to 3679 in ‘Gene 1,2,3’ clearly
differentiated the EHV-1 isolate obtained from a case of perinatal foal mortality from isolates obtained from abortion cases.
This primer pair needs to be exploited more extensively for use as a potential marker for differentiating the EHV-1 isolates,
mainly the abortion cases from perinatal foal mortality ones. Restriction endonuclease studies done with PCR product of all
the isolates with various primer pairs did not reveal any changes in the position or number of RE sites present in the products
amplified, indicating no variation in different RE sites within the amplified PCR products. However, this study clarified
that all the Indian isolates belonged to the IP group of EHV-1. 相似文献
132.
为了探索脾酪氨酸激酶(Syk)是否参与酿酒酵母甘露聚糖(S.c M)诱导绵羊瘤胃上皮细胞(ORECs)β-防御素-1(SBD-1)表达的过程,首先利用免疫组化、RT-PCR和免疫荧光等方法检测Syk在ORECs内的表达情况;然后采用qPCR和Western blot方法检测S.c M刺激ORECs后Syk的表达变化,同时用Western blot方法检测Syk的磷酸化水平;接着用3条Syk特异性siRNAs(#1、#2和#3)转染ORECs 24 h后,qPCR检测Syk mRNA的表达变化,筛选出干扰效果最佳的Syk siRNA;最后用效果最佳的siRNA和Syk特异性抑制剂R406分别处理ORECs后,采用qPCR和ELISA检测SBD-1的表达变化,以确定Syk在S.c M诱导SBD-1表达过程中的作用。结果显示:Syk在ORECs内表达;且S.c M刺激ORECs后Syk的mRNA和蛋白表达水平显著高于未刺激组(P<0.01或P<0.05),S.c M刺激ORECs不同时间(5、15、30、45和60 min)均能使Syk发生磷酸化,且刺激15 min后磷酸化水平达到最大(P<0.01);此外,Syk的3条特异性siRNAs转染ORECs后Syk的表达均降低,且Syk siRNA#2的抑制效果最明显(P<0.01);同时Syk siRNA#2和R406均能极显著降低S.c M诱导ORECs SBD-1的表达(P<0.01)。上述结果表明,Syk参与S.c M诱导ORECs SBD-1的表达。 相似文献
133.
为探究蒲公英属植物亲缘关系,本研究对13种蒲公英属(Taraxacum. F. H. Wigg.)植物进行了核型似近系数聚类分析,并计算了物种间遗传距离。结果表明:当核型似近系数接近0.6960时,13种蒲公英可以聚为4大类群;当核型似近系数接近0.4641时,13种蒲公英共属一类。异苞蒲公英与狭戟片蒲公英的亲缘关系最近,其似近系数最大,为0.9969,核型进化距离最小,为0.0031;多裂蒲公英和亚洲蒲公英的亲缘关系最远,似近系数为0.3343,核型进化距离为1.0959。本研究结果为蒲公英属植物的亲缘关系辨析、种质鉴定及物种进化分析提供依据。 相似文献
134.
ZHANG Mei ZHOU Ling-ling ZHANG Miao-miao ZHONG Xin-xian SHAO Jun FAN Li-na GENG Peng-rui LI Yi-dan LI Yan LIAO He-rong 《中国畜牧兽医》2017,44(7):2050-2056
In order to investigate the molecular mechanism of stunted growth testis of chicken (♂) and quail (♀) hybrids. 84 testicular tissue samples of New Roman cocks, male Korean quails and chicken-quail hybrids at different developmental stages were collected,the mRNA expression of Bcl-2 and PCNA genes in testicular tissue of cocks, quails and chicken-quail hybrids at different growth stages were detected using Real-time PCR. The results showed that the Bcl-2 and PCNA genes mRNA expression patterns in testes of chickens and quails at different growth stages were similar.The Bcl-2 gene was fluctuated in a whole, and decreased to the lowest value, then recovered rapidly and remained at a high level. The PCNA gene had a very significant peak value.Compared with the chicken and quail,the expression of Bcl-2 and PCNA genes mRNA in hybrids had no obvious change, which indicated that the pattern of the Bcl-2 gene regulation apoptosis in testis was different from chicken and quail at the hybrid testicular development process, and there was no obvious cell appreciation process.It was suggested that the molecular influencing factors of testicular dysplasia of chicken and quail hybrids were related to the abnormal expression of Bcl-2 and PCNA genes mRNA in testes.The results provided an important reference for the further study of the mechanism of testicular dysplasia between chicken and quail interspecific hybrids. 相似文献
135.
136.
为比较5种弓形虫抗原的诊断效果,建立实用的羊弓形虫病诊断方法,本研究制备了弓形虫速殖子全虫抗原和4个重组蛋白(GRA1、MIC3、MAG、BAG1),正交试验比较其免疫反应性,从中筛选出相对优势抗原并建立羊弓形虫病间接ELISA(iELISA)诊断方法,用于检测弓形虫特异的IgG抗体。研究结果表明:除BAG1外上述4种抗原均具有较好的免疫反应性,综合考虑选择致密颗粒蛋白1(GRA1)作为诊断抗原建立了GRA1-iELISA,其检测弓形虫抗体灵敏度大于1∶100(血清稀释度),且不与羊莫氏巴贝斯虫、吕氏泰勒虫、捻转血毛线虫阳性血清发生交叉反应,特异性良好;运用建立的方法和改良凝集试验分别对采自山羊屠宰场的80份血清样品进行检测,测得的弓形虫感染阳性率分别为28.75%(23/80)和31.25%(25/80),二者总符合率为82.5%。本研究建立的ELISA检测方法对羊弓形虫病的诊断以及商业化试剂盒的开发具有重要参考价值。 相似文献
137.
138.
Woochul Chang Chang Youn Lee Jun-Hee Park Moon-Seo Park Lee-So Maeng Chee Soon Yoon Min Young Lee Ki-Chul Hwang Yong-An Chung 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):69-76
The use of mesenchymal stem cells (MSCs) has emerged as a potential new treatment for myocardial infarction. However, the poor viability of MSCs after transplantation critically limits the efficacy of this new strategy. The expression of microRNA-210 (miR-210) is induced by hypoxia and is important for cell survival under hypoxic conditions. Hypoxia increases the levels of hypoxia inducible factor-1 (HIF-1) protein and miR-210 in human MSCs (hMSCs). miR-210 positively regulates HIF-1α activity. Furthermore, miR-210 expression is also induced by hypoxia through the regulation of HIF-1α. To investigate the effect of miR-210 on hMSC survival under hypoxic conditions, survival rates along with signaling related to cell survival were evaluated in hMSCs over-expressing miR-210 or ones that lacked HIF-1α expression. Elevated miR-210 expression increased survival rates along with Akt and ERK activity in hMSCs with hypoxia. These data demonstrated that a positive feedback loop involving miR-210 and HIF-1α was important for MSC survival under hypoxic conditions. 相似文献
139.
Janusz A Madej Jan P Madej Piotr Dziegiel Bartosz Pula Marcin Nowak 《Acta veterinaria Scandinavica》2013,55(1):73
Background
The study aimed at examining hypoxia-inducible factor (HIF)1α expression in adenocarcinomas and adenomas in bitches in regard to tumour malignancy grade, proliferation, apoptosis and vascularisation. Therefore, paraffin sections of 15 adenomas and 64 adenocarcinomas sampled from 79 dogs aged 6 to 16 years were analysed.Results
A significantly higher HIF-1α expression was noted in adenocarcinomas in comparison to adenomas (P < 0.0004). Moreover, HIF-1α expression in adenocarcinomas correlated positively with tumour malignancy grade (r = 0.59, P < 0.05), Ki-67 antigen expression (r = 0.43; P < 0.0005), TUNEL-positive cells (r = 0.62, P < 0001) and tumour vascularity measured by quantification of vessels characterized by the expression of von Willebrand Factor (r = 0.57, P < 0.05).Conclusion
Results of this study indicate a similar biological role of HIF-1α in dogs and in humans, which may confirm suitability of the animal model in investigations on progression of tumours in humans. 相似文献140.
动物被毛生长是一个复杂的过程,受遗传、内分泌、营养及外界条件等各种因素的影响。而胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)是一种具有促进细胞增殖、分化,调节物质代谢等多种生物活性的多肽分子。研究结果发现,IGF-1对被毛/毛发生长的影响不仅局限于自身,同时介导一些细胞因子对被毛生长的调节作用。为阐明IGF-1在被毛/毛发生长方面的重要作用,文章就国内外IGF-1对动物被毛生长影响的研究进展进行综述。 相似文献